Biogen Idec's long-acting beta interferon moves ahead in MS

The regulatory authorities in the US and EU have both accepted Biogen Idec's marketing application for long-acting multiple sclerosis (MS) drug Plegridy, setting up possible approvals in early- to mid-2014.

Plegridy (peginterferon beta-1a) is a new form of Biogen Idec's blockbuster MS treatment Avonex (interferon beta-1a), which remains the company's biggest product with sales of $2.91bn last year. The company had hoped for a priority review by the FDA, but instead Plegridy will be considered by the agency in its standard review period of around 10 months.

The submission was based on the results from the first year of the phase III ADVANCE study which demonstrated that Plegridy met its objectives by significantly reducing disease activity in MS patients, cutting relapses, disability progression and brain lesions compared to placebo. It also had a favourable safety and tolerability profile in the study, which will be carried out over two years.

The benefits of Plegridy are that it will require less frequent injections than Avonex and will be administered subcutaneously rather than intramuscularly, so should be less painful. The new product is given once every two or four weeks, while Avonex is administered once-weekly.

Biogen Idec has already extended the Avonex franchise with a new pen injector device which rolled out in the UE and EU last year, but Plegridy is a much more significant development as it is a new molecular entity (NME) and therefore extends the patent life of the company's interferon beta franchise.

The main substance patent on Avonex will expire at the end of this year and, while Biogen Idec has suggested it has additional protection on the drug out to 2026 via a 'use' patent, this is being challenged in the courts.

Approval of Plegridy would help the company maintain its interferon franchise as it simultaneously grows its other MS treatments, including the orally-active Tecfidera (dimethyl fumarate), which has been tipped to dominate the MS market in the coming years with peak sales in excess of $3bn a year.

Biogen Idec's also sells Tysabri (natalizumab) for MS, which is expected to remain an important treatment option for some patients, and is also bringing a new anti-CD-25 antibody called daclizumab through late-stage development.